The Combined Effect of Spin-Transfer Torque and Voltage-Controlled Strain Gradient on Magnetic Domain-Wall Dynamics:Toward Tunable Spintronic Neuron

Magnetic domain wall(DW), as one of the promising information carriers in spintronic devices, have been widely investigated owing to its nonlinear dynamics and tunable properties. Here, we theoretically and numerically demonstrate the DW dynamics driven by the synergistic interaction between current-induced spin-transfer torque(STT) and voltage-controlled strain gradient(VCSG) in multiferroic heterostructures. Through electromechanical and micromagnetic simulations, we show that a desirable strain gradient can be created and it further modulates the equilibrium position and velocity of the current-driven DW motion. Meanwhile, an analytical Thiele's model is developed to describe the steady motion of DW and the analytical results are quite consistent with the simulation data. Finally, we find that this combination effect can be leveraged to design DW-based biological neurons where the synergistic interaction between STT and VCSG-driven DW motion as integrating and leaking motivates mimicking leaky-integrate-and-fire(LIF) and self-reset function. Importantly, the firing response of the LIF neuron can be efficiently modulated, facilitating the exploration of tunable activation function generators, which can further help improve the computational capability of the neuromorphic system.

双向主客体作用促进水溶液中选择性光催化CO_(2)还原与醇氧化

CO_(2)还原与H_(2)O氧化耦合被认为是将太阳能转化为化学能的理想方法.然而,H_(2)O氧化反应的显著动力学障碍限制了该类反应的转化效率.此外,额外的电子牺牲剂的消耗不仅在经济上不可行,而且浪费了光生空穴的氧化能力.因此,将CO_(2)还原与有机物的有效氧化相结合将是有效利用太阳能和解决能源危机的有效途径之一.对于包含光敏剂、催化剂和反应底物的离散光催化体系来说,电子转移效率主要由离散组分之间的扩散过程控制.为了提高光反应组分之间的电子转移效率,研究人员尝试通过共价键在催化剂和光敏剂之间建立“桥梁”,从而获得更快的电子转移速率.然而,该类体系存在合成过程复杂、共价键断裂及使用贵金属等问题.与共价键相比,非共价体系更便于合成,且具有更好的稳定性.本文利用双向主客体相互作用构筑高效光催化体系,其中水溶性β-环糊精修饰的CdS纳米晶与CoTPP(助催化剂)和有机醇(反应底物)均通过非共价主客体作用连接,促使光生电子和光生空穴的同步快速消耗.核磁共振氢谱结果表明,环糊精作为主体分子可以识别客体分子四苯基卟啉钴与呋喃醇.利用Job曲线测得环糊精与四苯基卟啉钴以及呋喃醇的键合比分别为2:1和1:1.紫外-可见吸收光谱结果表明,环糊精与四苯基卟啉钴以及呋喃醇之间存在不同强度的主客体键合.光催化CO_(2)还原反应与呋喃醇氧化性能测试结果表明,与无配体的Cd S纳米晶(CdS-BF_(4))以及其它配体(油酸、2-巯基乙醇和硫代甘油)修饰的Cd S纳米晶相比,环糊精修饰的CdS-CD纳米晶在水相中表现出更高的CO_(2)还原为HCOOH的活性与选择性,同时,表现出最佳的呋喃醇氧化活性与选择性.相反,表面无配体的Cd S-BF4纳米晶活性较低,且有严重的析氢副反应发生.为了更好地理解双向主客体相互作用对光反应性能的贡献,利用一系列稳态和瞬态荧光光谱实验研究了三个组分之间的电子转移过程.结果表明,CdS-CD与Co TPP之间以及Cd S-CD与呋喃醇之间的双向主客体相互作用可以有效促进这些组分之间的电子转移过程.原位漫反射傅立叶变换红外光谱和密度泛函理论研究表明,随着光辐射时间的增加,HCOO*信号逐渐增强.电子顺磁共振波谱结果表明,在光催化呋喃醇氧化的过程中产生了呋喃醇苄基自由基.在以上光还原和光氧化的全反应过程中,双向主客体作用同时将助催化剂和反应物聚集在吸光物质Cd SNCs表面,这对于促进快速电子/空穴转移和随后的氧化还原反应发挥着关键作用.综上所述,选择合适的有机物不仅可以促进光还原反应的发生,还可以生产更高附加值的化学品.本文采用双向主客体策略构建新型的人工光合作用系统,为构建具有实际应用潜能的人工光合作用系统提供了新的思路.

吡咯烷二硫代氨基甲酸酯对TGF-β2诱导人晶状体上皮细胞EMT的抑制作用

目的:探究吡咯脘二硫代氨基甲酸酯(PDTC)对转化生长因子-beta2(TGF-β2)诱导人晶状体上皮细胞(LECs)上皮-间充质转化(EMT)的逆转机制。方法:TGF-β2诱导人晶状体上皮细胞EMT,并给予不同浓度PDTC处理TGF-β2诱导的LECs。CCK-8、划痕试验检测细胞增殖与迁移,Western Blot检测EMT标志物E-cadherin、α-SMA和NF-κB信号传导通路相关蛋白表达,以及凋亡相关蛋白BAX、BCL-2、Caspase-3、细胞周期蛋白D_1的表达。结果:TGF-β2处理组细胞增殖和迁移活力明显高于未添加TGF-β2的实验组;E-cadherin表达下调,α-SMA表达上调。在TGF-β2的作用下NF-κB p65和磷酸化的NF-κB p65表达增加(P<0.05)且在TGF-β210 ng/mL刺激浓度时LECs表现出较强的增殖活力和迁移能力。PDTC逆转EMT和诱导细胞凋亡的机制研究表明,PDTC干预处理后细胞活力和迁移能力都显著降低,PDTC抑制IκB的磷酸化进而抑制NF-κB核移位,NF-κB信号通路中NF-κBp65/p-NF-κB p65、Iκκ-α/p-Iκκ-α表达下调(P<0.05),诱导促凋亡蛋白BAX/Caspase-3表达上调、抑凋亡蛋白BCL-2、细胞周期蛋白Cyclin D_1表达下调,NF-κB/IκB mRNA表达下调,凋亡相关mRNA BAX表达上调BCL-2表达下调。结论:PDTC可显著逆转由TGF-β2诱导的LECs细胞EMT过程,可能与抑制NF-κB信号通路活化使NF-κB p65/IκB/Iκκ-α表达降低以及激活凋亡相关蛋白表达有关,PDTC可通过抑制NF-κB信号通路达到逆转EMT的进程并使异常增殖的细胞发生凋亡,这将为后发性白内障的治疗提供新的潜在的治疗药物。

A case of primary malignant fibrous histiocytoma of the pancreas: CT and MRI findings

Primary malignant fibrous histiocytoma (MFH) of the pancreas is rare and a distinct clinical entity. We report a case of recurrence of pancreatic MFH with computed tomography (CT) and magnetic resonance imaging (MRI) findings. A 67-year-old man presented with a history of decreased body weight over the past 6 mo. Abdominal CT revealed a large, multilocular cystic mass in the head of the pancreas with obvious atrophy in the body and tail of the pancreas. After 6 mo postoperatively, MRI demonstrated a recurrent large mass in the primary area of the head of the pancreas. The lesion was heterogeneous, hypointense to the liver on T1-weighted imaging, and heterogeneously hyperintense to the liver with a hypointense area in the central part of the tumor on fat-saturated T2-weighted imaging. Contrast- enhanced T1-weighted imaging demonstrated a large multilocular cystic mass with a cystic wall, fibrous septa and enhancement of solid components. To the best of our knowledge, this is the first report on recurrence of primary MFH of the pancreas, and the first with MRI findings.

Gastrodin protects retinal ganglion cells through inhibiting microglial-mediated neuroinflammation in an acute ocular hypertension model

AIM：To investigate the neuroprotective effect of gastrodin on retinal ganglion cells（RGCs）in an acute ocular hypertension（AOH）rat model and to identify its possible mechanism.METHODS：AOH rat model was performed in a randomly selected eye by anterior chamber perfusion and either received an intraperitoneal injection with various concentrations of gastrodin or normal saline.After 2wk,the rats were sacrificed.Fluoro Gold was used to label survival RGCs.Immunostaining with anti-Iba1 in the retinal flat mounts to calculate the microglia density in the ganglion cell layer（GCL）.Changes in microglial cytokines,tumour necrosis factor-alpha（TNF-α）and inducible NO synthase（i NOS）were examined with Western blot and reverse transcriptionquantitative polymerase chain reaction.Expression levels of total and phosphorylated p38 mitogen activated protein kinase（MAPK）were determined by Western blot.RESULTS：Results showed that AOH induced significant loss of RGCs and severe microglia activation in the GCL.Besides,AOH increased the phosphorylation of p38 MAPK and promoted the release of microglial cytokines in the retinas.Intraperitoneal injection with dose-dependent gastrodin significantly reduced the loss of RGCs and inhibited retinal microglia activation,accompanied with the decreased expression levels of microglial cytokines and p38 MAPK phosphorylation.CONCLUSION：Gastrodin exerts a neuroprotective effect on RGCs in an acute glaucoma animal model viainhibiting microglia activation and microglial-mediated neuroinflammation.The finding demonstrates the potential application of gastrodin in the neuroprotective therapy of acute glaucoma and other retinal neurodegenerative diseases characterized by microglia activation and RGCs death.

Effects of groundwater level on vegetation in the arid area of western China

At present,investigation about the relationship between the change of groundwater level and vegetation mostly focuses on specific watersheds,i.e.limited in river catchment scale.Understanding the change of groundwater level on vegetation in the basin or large scale,be urgently needed.To fill this gap,two typical arid areas in the west of China(Tarim Basin and Qaidam Basin)were chosen the a typical research area.The vegetation status was evaluated via normalization difference vegetation index(NDVI)from 2000 to 2016,sourced from MODN1F dataset.The data used to reflect climate change were download from CMDSC(http://data.cma.cn).Groundwater level data was collected from monitor wells.Then,the relationship of vegetation and climate change was established with univariate linear regression and correlation analysis approach.Results show that:Generally,NDVI value in the study area decreased before 2004 then increased in the research period.Severe degradation was observed in the center of the basin.The area with an NDVI value>0.5 decreased from 12%to 6%between 2000 and 2004.From 2004 to 2014,the vegetation in the study area was gradually restored.The whole coverage of Qaidam Basin was low.And the NDVI around East Taigener salt-lake degraded significantly,from 0.596 to 0.005,2014 and 2016,respectively.The fluctuation of groundwater level is the main reason for the change of surface vegetation coverage during the vegetation degradation in the basin.However,the average annual precipitation in the study area is low,which is not enough to have a significant impact on vegetation growth.The annual average precipitation showed an increase trend during the vegetation restoration in the basin,which alleviates the water shortage of vegetation growth in the region.Meanwhile,the dependence of surface vegetation on groundwater is obviously weakened with the correlation index is−0.248.The research results are of some significance to eco-environment protection in the arid area of western China.

Aqueous proinflammatory cytokines in acute primary angle-closure eyes

AIM：To evaluate changes of proinflammatory cytokines in aqueous humor of patients with acute primary angleclosure（APAC） and age-related cataracts. METHODS：Twenty eyes of 20 APAC patients and 15 eyes of 15 age-related cataract patients were included in this cross-sectional study. Aqueous humor samples were collected prospectively. The levels of 20 proinflammatory cytokines were evaluated in the aqueous humor of the APAC and cataract patients using the multiplex bead immunoassay technique. Clinical data were collected for correlation analysis.RESULTS：Seven of the 20 proinflammatory cytokines included in the magnetic bead panel were detectable in both APAC eyes and cataract eyes：interleukin（IL）-10, IL-12, IL-15, IL-21, IL-6, chemokine（C-C motif） ligand 20, and tumor necrosis factor alpha（TNF-α）. IL-27 was only detectable in APAC eyes. Compared with the cataract eyes, the APAC eyes had significantly elevated concentrations of IL-12（P=0.036）, IL-15（P=0.001）, IL-6（P=0.012）, and IL-27（only detectable in APAC eyes）. Age was positively correlated with IL-12（P=0.022） and IL-6（P=0.037）, and time elapsed between APAC onset and aqueous humor samples collection was positively correlated with IL-15（P=0.037）, IL-27（P=0.040）, and TNF-α（P=0.042）.CONCLUSION：Several proinflammatory cytokines including IL-12,IL-15, IL-6 and IL-27, were elevated in the APAC eyes and may be implicated in its pathologic mechanism.

Relationship of underground water level and climate in Northwest China’s inland basins under the global climate change:Taking the Golmud River Catchment as an example

To identify the response of groundwater level variation to global climate change in Northwest China’s inland basins,the Golmud River Catchment was chosen as a case in this paper.Approaches of time series analysis and correlation analysis were adopted to investigate the variation of groundwater level influenced by global climate change from 1977 to 2017.Results show that the temperature in the Golmud River Catchment rose 0.57℃ every 10 years.It is highly positive correlated with global climate temperature,with a correlation coefficient,0.87.The frequency and intensity of extreme precipitation were both increased.Generally,groundwater levels increased from 1977 to 2017 in all phreatic and confined aquifers and the fluctuation became more violent.Most importantly,extreme precipitation led to the fact that groundwater level rises sharply,which induced city waterlogging.However,no direct evidence shows that normal precipitation triggered groundwater level rise,and the correlation coefficients between precipitation data from Golmud meteorological station located in the Gobi Desert and groundwater level data of five observation wells are 0.13,0.02,−0.11,0.04,and−0.03,respectively.This phenomenon could be explained as that the main recharge source of groundwater is river leakage in the alluvial-pluvial Gobi plain because of the high total head of river water and goodness hydraulic conductivity of the vadose zone.Data analysis shows that glacier melting aggravated because of local temperature increased.As a result,runoff caused groundwater levels to ascend from 1977 to 2017.Correlation coefficients of two groundwater wells observation data and runoff of Golmud River are 0.80 and 0.68.The research results will contribute to handling the negative effects of climate change on groundwater for Northwestern China.

Diagnosis of cytomegalovirus encephalitis using metagenomic nextgeneration sequencing of blood and cerebrospinal fluid:A case report

BACKGROUND Cytomegalovirus(CMV)infections in the population are mostly subclinical,inapparent,or latent.However,it is rare in brain tissue.Most reported CMV encephalitis cases were patients with immunodeficiency.The diagnosis and detection rate of CMV encephalitis in patients with normal immune function needs to be further improved.CASE SUMMARY An 86-year-old male was admitted due to a sudden onset of unconsciousness for 3 h.The patient developed status epilepticus and was relieved after antiepileptic treatment.Encephalitis was considered due to the high signals of diffusionweighted imaging sequences in the right central region by magnetic resonance imaging.Metagenomic next-generation sequencing(mNGS)of blood and cerebrospinal fluid revealed CMV,with unique reads number being 614 and 1,respectively.Simultaneous quantitative PCR results showed CMV positive in blood samples and negative in cerebrospinal fluid samples.The patient was finally diagnosed as CMV encephalitis with status epilepticus.After the antiviral,hormonal,andγ-globulin pulse therapy,the patient’s condition improved,and he was finally discharged.CONCLUSION mNGS could be a reliable approach for the diagnosis of CMV encephalitis,with high efficiency,sensitivity,and specificity.

Recurrent endophthalmitis caused by intraocular eyelashes

Dear Editor,The presence of intraocular eyelashes following a penetrating injury or surgical intervention is rarely encountered and is usually an incidental finding in clinic1' There is significant individual difference in how the eye responds to intraocular eyelashes.

Perenniality:From model plants to applications in agriculture

To compensate for their sessile nature,plants have evolved sophisticated mechanisms enabling them to adapt to ever-changing environments.One such prominent feature is the evolution of diverse life history strategies,particularly such that annuals reproduce once followed by seasonal death,while perennials live longer by cycling growth seasonally.This intrinsic phenology is primarily genetic and can be altered by environmental factors.Although evolutionary transitions between annual and perennial life history strategies are common,perennials account for most species in nature because they survive well under year-round stresses.This proportion,however,is reversed in agriculture.Hence,perennial crops promise to likewise protect and enhance the resilience of agricultural ecosystems in response to climate change.Despite significant endeavors that have been made to generate perennial crops,progress is slow because of barriers in studying perennials,and many developed species await further improvement.Recent findings in model species have illustrated that simply rewiring existing genetic networks can lead to lifestyle variation.This implies that engineering plant life history strategy can be achieved by manipulating only a few key genes.In this review,we summarize our current understanding of genetic basis of perenniality and discuss major questions and challenges that remain to be addressed.

Combining single-cell RNA sequencing with spatial transcriptome analysis reveals dynamic molecular maps of cambium differentiation in the primary and secondary growth of trees

Primary and secondary growth of the tree stem are responsible for corresponding increases in trunk height and diameter.However,our molecular understanding of the biological processes that underlie these two types of growth is incomplete.In this study,we used single-cell RNA sequencing and spatial transcriptome sequencing to reveal the transcriptional landscapes of primary and secondary growth tissues in the Populus stem.Comparison between the cell atlas and differentiation trajectory of primary and secondary growth revealed different regulatory networks involved in cell differentiation from cambium to xylem precursors and phloem precursors.These regulatory networks may be controlled by auxin accumulation and distribution.Analysis of cell differentiation trajectories suggested that vessel and fiber development followed a sequential pattern of progressive transcriptional regulation.This research provides new insights into the processes of cell identity and differentiation that occur throughout primary and secondary growth of tree stems,increasing our understanding of the cellular differentiation dynamics that occur during stemgrowth in trees.

超深井压裂对管内瞬态波动压力的影响研究

在压裂过程中,由于压裂液流量大且压力高,油管容易失效。如果压裂液流动边界瞬间发生变化,将直接影响油管内压力和速度的突变,导致油管失效甚至断裂,造成严重的井筒完整性问题。该文针对超深井高泵压大排量压裂过程中瞬时停泵工况,建立了压裂管柱内流体水击计算模型,讨论了采用不同直径和壁厚的管柱组合造成的局部摩阻影响,得到了变截面处局部摩阻、停泵时间以及压裂液排量变化对井口压力的影响。研究发现,停泵后,井口压力下降,在平衡压力值附近发生波动,波动幅值逐渐减小,直至衰减至平衡压力。若不考虑局部摩阻,压力波传播速度较快,幅度偏大,稳定至平衡压力所需时间滞后。压裂液的排量增大时,压力波速增加,会提前出现压力首波。排量越大,压力首波的波动幅度就越大。停泵时间越短,压力变化越大,压力首波出现越快,压力峰值越大。

A Single-Cell RNA Sequencing Profiles the Developmental Landscape of Arabidopsis Root

Cells of eukaryotic multicellular organisms have inherent heterogeneity.Recent advances in single-cell gene expression studies enable us to explore transcriptional regulation in dynamic development processes and highly heterogeneous cell populations.In this study,using a high-throughput single-cell RNA-sequencing assay,we found that the cells in Arabidopsis root are highly heterogeneous in their transcriptomes.A total of 24 putative cell clusters and the cluster-specific marker genes were identified.The spatial distribution and temporal ordering of the individual cells at different developmental stages illustrate their hierarchical structures and enable the reconstruction of continuous differentiation trajectory of root development.Moreover,we found that each root cell cluster exhibits distinct patterns of ion assimilation and hormonal responses.Collectively,our study reveals a high degree of heterogeneity of root cells and identifies the expression signatures of intermediate states during root cell differentiation at single-cell resolution.We also established a web server(http://wanglab.sippe.ac.cn/rootatlas/)to facilitate the use of the datasets generated in this study.

水稻OsSPL12与GW5存在共进化并协同决定粒型

粒型是决定水稻产量和稻米品质的关键因素之一.本研究发现水稻转录因子SQUAMOSA promoter-binding protein-like 12 (Os SPL12)与粒型调控关键基因Grain Width 5(GW5)存在协同进化,最终导致籼粳稻的粒型差异.本研究首先通过群体遗传学与功能学的双重验证,表明籼稻Os SPL12转录激活域的一个单核苷酸多态性(SNP)SNP1066能显著改变Os SPL12的转录活性,使籼稻Os SPL12对粒宽起到抑制作用.随后通过幼穗组织的转录组学分析发现,粒宽调控关键基因GW5特异受籼稻Os SPL12调控. GW5基因启动子区域富含SPLs蛋白的识别与结合基序(GTAC),提示籼稻Os SPL12可能通过直接调控GW5表达最终抑制粒宽.进一步结合"3000份水稻基因组"数据分析发现籼稻Os SPL12与籼稻GW5等位基因的组合显著抑制粒宽.此前的研究表明粳稻中GW5的低表达主要是由于其启动子上游约5-kb处存在一段1212-bp的缺失,本研究进一步通过实验证明籼稻Os SPL12与1212-bp以增强子-启动子的方式促进GW5的表达.综上所述,本研究阐明了水稻驯化中Os SPL12与GW5存在共进化并协同决定了水稻粒型,证明了Os SPL12在籼粳稻粒型分化上的重要作用.

Challenges and strategies for ultrafast aqueous zinc-ion batteries

With the rising demand for fast-charging technology in electric vehicles and portable devices,significant efforts have been devoted to the development of the highrate batteries.Among numerous candidates,rechargeable aqueous zinc-ion batteries(ZlBs)are a promising option due to its high theoretical capacity,low redox potential of zinc metal anode and inherent high ionic conductivity of aqueous electrolyte.As the strong electrostatic interaction between Zn^(2+)and host generally leads to sluggish electrode kinetics,many strategies have been proposed to enhance fast(dis)charging performance.Herein,we review the state-of-the-art ultrafast aqueous ZIBs and focus on the rational electrode-designing strategies,such as crystal structure engineering,nanostructuring and morphology controlling,conductive materials introducing and organic molecule designing.Recent research directions and future perspectives are also proposed in this review.

Plant non-coding RNAs and epigenetics

Epigenetics plays a large role in various aspects of plant biology,including development,response to biotic and abiotic stresses,silencing of transposable elements,and maintenance of genome stability.In plants,epigenetic regulation involves histone and DNA modifications and noncoding RNAs including small RNAs(s RNAs)and long noncoding RNAs(lnc RNAs).This issue of Science China Life Sciences includes five review articles and eight

The role of miRi56 in rejuvenation in Arabidopsis thaliana

Rejuvenation refers to the process enabling plants to regain physlological and molecular characteristics lost after entering the adult phase. The underlying molecular mechanism is pooly under-stood. Previous studies have revealed that mi-CroRNA156 (miR156) is highly accumulated at juvenile stage and maintains juvenile traits by repressing a group of SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors. Here, we found that induction of miR156 expression in adult leaves can only restore some aspects of juvenile traits, such as loss of epidermal leaf hairs on the lower side of leaves and absence of serration at the leaf edges, but is incapable of delaying flowering and promoting adventitious root production.

Targeted Genes Sequencing Identified a Novel 15 bp Deletion on GJA8 in a Chinese Family with Autosomal Dominant Congenital Cataracts

Background： Congenital cataract （CC） is the leading cause of visual impairment or blindness in children worldwide. Because of highly genetic and clinical heterogeneity, a molecular diagnosis of the lens disease remains a challenge. Methods： In this study, we tested a three-generation Chinese family with autosomal dominant CCs by targeted sequencing of 45 CC genes on next generation sequencing and evaluated the pathogenicity of the detected mutation by protein structure, pedigree validation, and molecular dynamics （MD） simulation. Results： A novel 15 bp deletion on GJA8 （c.426_440delGCTGGAGGGGACCCT or p. 143147delLEGTL） was detected in the family. The deletion, concerned with an in-frame deletion of 5 amino acid residues in a highly evolutionarily conserved region within the cytoplasmic loop domain of the gap junction channel protein connexin 50 （CxS0）, was in full cosegregation with the cataract phenotypes in the family but not found in 1100 control exomes. MD simulation revealed that the introduction of the deletion destabilized the Cx50 gap junction channel, indicating the deletion as a dominant-negative mutation, Conclusions： The above results support the pathogenic role of the 15 bp deletion on GJA8 in the Chinese family and demonstrate targeted genes sequencing as a resolution to molecular diagnosis of CCs.

Regulation of Flowering Time by MicroRNAs

The shoot apical meristem（SAM） continuously produces lateral organs in plants.Based on the identity of the lateral organs,the life cycle of a plant can be divided into two phases： vegetative and reproductive.The SAM produces leaves during the vegetative phase,whereas it gives rise to flowers in the reproductive phase（reviewed in Poethig,2003）.The floral transition,namely the switch from vegetative to reproductive growth,